The present invention is directed to technology used in a radio communication device to derive information about the signals active in a radio frequency band where the radio communication device is operating, such as an unlicensed radio frequency band shared by many different devices.
In certain radio communication systems, it would be desirable to know whether and what types of other signals or devices are active. For example, an unlicensed radio frequency band is, by its nature, free to be used by any device that emits radio energy within certain power levels in that part of the allocated spectrum. It is possible that many devices would share the unlicensed frequency band at the same time, potentially causing interference with each other. Under these circumstances, what would be useful is to provide the capability of processing signals that represent activity in the frequency spectrum over a time interval to derive information about the basic characteristics of those signals in order to identify or classify them.